Errors in computer programs are called software bugs. The bug causes the software program to behave in an unexpected manner with incorrect or no response, causing the eventual failure of the program.
What causes bugs in software?
Occurrence of bugs in software is a consequence of several factors which are due to human errors, coding practices, tools, etc. Here's a brief description of some of them:
Misunderstanding of requirements:This is a consequence of incomplete understanding and the resultant coverage of all the requirements asked of a software product. The developers create a product which is incomplete. A lack of communication in a team of developers results in a scenario, where the product developed by one developer may be unknowingly modified in a harmful way by another developer working in the same team.
Time constraints: Lack of adequate time has a bearing on the quality of the application being generated, as the developers miss out on some crucial loopholes in the basic functionalities of the product. Many a times, in the event of looming project deadlines, the testing team is not able to execute all tests on time. Sometimes the developer team is not able to rectify all the defects reported by the testing team.
Lack of experience: As in every field, experience always counts and it always has a saying in the quality of the product. This is true for both the developer and testing teams. It is not uncommon for inexperienced professionals from these streams to miss out on crucial details which may also be a result of faulty debugging tools. They also suffer from lack of exposure to unhandled exceptions.
Faulty third party tools: Debugging tools like HTML editors and compilers consist of dll files composed by other developers and glitches present in them may alter the coding in the product during testing. Thus inadvertently causing errors in the product about to be released for launch.
Changes at the 11th hour : Last minute changes in requirement of software , may result in modifying the original code and result in defects.
Bugs due to upgrade in version: The testers miss out on testing each and every software module for seamless linking which should come with the installation of new upgrades.
Bugs with malicious intent: Unscrupulous elements from the unethical world of hacking devise new bugs which can harm the working of the software through attachment with downloaded files or upgrades.
Prevention of bugs/Debugging
Consistency in programs: Programs are written to self verify the inconsistencies in the code comprised of data. On the identification of a bug, the program gets automatically halted for correction. As an alternative, it can inform the developer about inconsistencies such as absence of mathematical operators in logical statements.
Code analysis: Based on the fact that developers tend to make the same follies while writing codes for software, code analysis tools run inspection test looking to identify potential defects in the code.
Diagnostic tools: Sometimes tools are embedded in the program to monitor those parts which are suffering bottlenecks and give assurances for authentic working of the software.